milling cutters

[BrokenBiker]

getting pretty close to having a working milling set up on the lathe...only anticipate doing small bits on there as i will only have about 80mm of travel in what would be the Y axis of a milling machine (will be up/down on my milling attachment), but the few projects i have in mind involve plunging and milling pockets.

would a 2 flute end mill be better for this as i notice the 4 flute end mills i have all have a dimple in the centre which prevents plunging past maybe 2mm at most.

 

[dieselsamurai]

I usually only use a 2 flute for Ali milling but they are ok for use as a drill in steel as that what I was taught , are you machining Ali or steel ? I have lots or 3 and 4 flute mills that will plunge and mill too so they are avaliable

this may be useful

 

[RichardM]

Two flute for plunging, do not climb mill. I would drill the initial hole and chain drill with a two flute undersize, then finish to size

 

[Kram]

would a 2 flute end mill be better for this as i notice the 4 flute end mills i have all have a dimple in the centre which prevents plunging past maybe 2mm at most.

Ah, the slot drill vs end mill problem! You just need to find four flute centre cutting.

2 flute is generally for non ferrous that benefit from wider chip clearance space, the flutes and the cutter are weaker, so not great for steel work.

Theres also 3 flute "throw away cutters".

 

[BrokenBiker]

First prototype project will be from aluminium, but i have projects in mi d that woukd need to be made from steel, brass, alloy steel and a bit of stainless so think I will either drill a pilot hole first or find some centre cutting end Mills

 

[6ply]

I like to use a ripper end mill wherever possible. Gets the job done faster.

 

[BrokenBiker]

I like to use a ripper end mill wherever possible. Gets the job done faster.

View attachment 510779

I doubt my lathe has the speeds/feeds to use something like that to its full potential

 

[6ply]

I doubt my lathe has the speeds/feeds to use something like that to its full potential

I find them easier on the machine as they cut much more efficiently than a plain end mill. Less effort feeding and lower vibration. Get yourself a small one, 10 or 12 mm diameter and give it a try. I've got some much larger ones if you decide to upgrade later!

 

[Seadog]

I doubt my lathe has the speeds/feeds to use something like that to its full potential

They need less power.
You will need to take a fine finishing cut with a full-lipped cutter to achieve a smooth finish if the piece requires it.

 

[Rrobson]

Plunge cutting with either an end mill (3/4 flutes generally) or a slot drill (2 flutes) will almost certainly throw the parts all over the place using a milling set up on a lathe. It will be seriously lacking the rigidity needed to keep the part in one place.

You can cut slots with an end mill by travelling it while simultaneously plunging, but this can be hard on the cutter, especially on wobbly machines.
Your best bet is to drill with conventional twist drill, then finish with either an end mill or slot drill.

 

[BrokenBiker]

Plunge cutting with either an end mill (3/4 flutes generally) or a slot drill (2 flutes) will almost certainly throw the parts all over the place using a milling set up on a lathe. It will be seriously lacking the rigidity needed to keep the part in one place.

You can cut slots with an end mill by travelling it while simultaneously plunging, but this can be hard on the cutter, especially on wobbly machines.
Your best bet is to drill with conventional twist drill, then finish with either an end mill or slot drill.

i guess ill find out shortly, but to be honest with a 995kg lathe, im not massively concerned about rigidity for making small parts...

 

[Rrobson]

Good luck, and go steady.

Machine rigidity can be an issue even when using a 5t milling machine, particularly when using slot drills and end mills like that…

 

[indykid]

i guess ill find out shortly, but to be honest with a 995kg lathe, im not massively concerned about rigidity for making small parts...

How well adjusted are the gibs? The bed casting might be heavy but a milling cutter will soon throw the compound and saddle about if the gibs are sloppy.

If you conventional mill and keep the cutting forces downward, you'll be in a far better position either way

 

[BrokenBiker]

How well adjusted are the gibs? The bed casting might be heavy but a milling cutter will soon throw the compound and saddle about if the gibs are sloppy.

If you conventional mill and keep the cutting forces downward, you'll be in a far better position either way

The compound wont be fitted...Gibson are adjusted pretty well, there's little to no backlash in either x or y and I went round the guys when I got the lathe and snugged then up where needed.